It's odd that it's leaking around the bolt head. Maybe the water pump housing is cracked. You might try wiping the area down and tighten that bolt up just a bit and see what happens. Run the engine a bit and see what happens. You can also pressurize the coolant system with some compressed air to see if that is were the leak actually is.
It's definetly not the water pump. If it were toast you'd see coolant coming out the weep holes.

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